W14 ... the postcode without a post office

Shut: the Olympia post office was inside a Costcutter store in Hammersmith Road

An entire London postcode has been left without a single post office for the first time since the capital was split into districts in 1857.

The last remaining branch in Olympia W14 shut down last month after the Costcutter supermarket in which it was housed stopped trading.

It comes ahead of the planned cull of another 169 branches across London designed to stem the Post Office's £150million-a-year losses.

Although the Post Office says it is "hopeful" of reopening the branch, campaigners say it marks the start of brutal cuts that will devastate dozens of communities.

The Olympia post office in Hammersmith Road serves the W14 population of 35,000, roughly the same as towns such as Boston in Lincolnshire, which has 22 post offices, Canterbury (21) and Bridgwater, Somerset (18).

Residents, who include former foreign secretary Lord Hurd, were promised the Costcutter would provide a full service when the last standalone post office in Blythe Road closed two years ago in the face of protests.

But after a Tesco Express opened next door last autumn it struggled to compete and went out of business last month. A notice on the door says: "The post office is now closed" .

A Post Office spokeswoman said: "As we have made clear in our proposals, we are committed to providing a post office in this area. We apologise to customers for the temporary closure of Hammersmith Road post office for reasons beyond our control and will resume service as soon as possible." Labour MP Andrew Slaughter, who is standing for the new Hammersmith constituency at the next election, said: "Even if they are saying this is still a functioning office, it could be years before it is open again."

Across London, dozens of demonstrations, petitions and campaigns are being organised to halt planned post office shutdowns.

Actor Tony Robinson is among those due to protest at the closure of his local branch in Formosa Street, Little Venice, by marching on Saturday from it to the suggested nearest alternative in St John's Wood, at least a mile away.

He said: "London is a series of villages and it is exactly the same as closing the post office for a country village. If you take it away what you are left with is just another characterless street."

Plans to run post office branches from council buildings such as libraries appear to have made little progress.